A multiple-energy X ray security inspection system refers to a new type of security inspection system developed based on a single-energy X ray security inspection system. The multi-energy X ray security inspection system can provide not only the shapes and contents of the objects under inspection, but also information reflecting the effective atomic numbers of the objects under inspection, so that the system can effectively determine whether the objects under inspection are organics or inorganics and display the objects on a color monitor with different colors. This can help operators to distinguish. Existing X ray security inspection systems provide two-dimensional or three-dimensional stereograms of luggage. Usually, objects in luggage are stacked disorderly, overlapping and obscuring each other, which brings difficulties in recognizing hazardous objects comprehensively, fast and effectively. Existing security inspection devices and methods can mark categories of objects with colors, but this can provide very little assistance. During the scanning procedure, screeners (the persons who judge images) have very little time (for example, 10 seconds) to check every image, and this also brings difficulties to the work of the screeners. Thus, there is an urgent need to provide a method and device for operating a CT-based (Computed Tomography based) three-dimensional image used for security inspection, which are capable of assisting screeners to judge images faster and thereby to increase the speed and accuracy of security inspection.
For obtaining of information about CT-based images, accuracy is preferred in industrial and medical applications, and images are mainly obtained from sectional slices. In the security inspection field, convenience and speed are the most important factors which need to be considered, because the screeners can have only about 10 seconds to check every image during the scanning procedure. Thus, in prior arts, it is still not possible to fast and accurately obtain information of target objects when CT-based security inspection is performed within a short time.